1. Field of the Invention
The present invention relates generally to RFID tag testing systems and, more specifically, to a system for repeatedly propelling a vehicle around a track to automate the process for testing an electronic toll collection reader and RFID tag system.
2. Description of the Background
Radio-frequency identification (RFID) entails the wireless use of radio waves between an RFID tag and a tag reader for the purpose of automatically identifying and tracking an object. The RFID tag includes a RFID tag, capable of receiving a wireless signal, termed an interrogating signal, and responding by emitting an identifying signal unique to the RFID tag. There are a variety of applications for this technology, and RFID tags can be attached to most anything including cash, clothing, merchandise, and can even be implanted in people. One well-known application in the automotive field is in electronic toll collection systems, such as (but not limited to) the E-ZPass™ system used on toll roads in several states in the mid-Atlantic and New England regions. These systems typically comprise one or more readers mounted above one or more toll lanes at the entrance to a toll road, bridge or the like, and emitting a radio signal that is readable by each RFID tag passing underneath in the toll lane. Other electronic toll collection systems utilize one or more readers mounted on or below the travel lane such that vehicles pass over or beside the readers as they travel through the toll plaza. Electronic toll collection systems allow motorists with a RFID tag from an issuing authority to pass through toll stations without making a physical transaction of cash, coins, tickets, etc. and without coming to a complete stop. The toll is paid via a prepaid account or credit card linked to an account, eliminating the need for an exchange of cash or coins. RFID-based toll collection systems have greatly improved the flow of traffic through the toll lanes servicing high traffic toll roads.
As RFID adoption grows, the need to validate tags for interoperability with readers from other vendors, and vice versa, and for conformance with specified wireless protocol increases. Largely as a result of conformance testing, RFID systems have significantly improved over the past several years. However, the current demand is driving mounting pressure to improve tag performance to achieve read rates closer to 100% at higher speeds, RFID test system designers face a significant challenge when attempting to meet the needs of this emerging market. Comprehensive RFID testing is complex, and entails a combination of conformance, interoperability and lifecycle testing. To be more specific, comprehensive RFID testing may require a testing system capable of moving an RFID tag beneath an antenna array at exactly one hundred miles an hour, a thousand times, followed by repeated at ninety miles an hour, eighty, etc. Thus, any designer of such a test system must provide a level of reliability higher than the tags being tested, yet allow accurate testing the operation of the RFID tag/reader combinations under repeated use at most any vehicle speed over extended (lifecycle) periods of time.
Accordingly, what is needed is a test system for precisely and reliably testing conformance, interoperability, lifecycle, range and accuracy of RFID tag and reader combinations over an exceedingly high number of passes (i.e., millions) and at precisely-controllable speeds. Moreover, a scalable test system design is needed to allow various types, sizes and numbers of RFID tags and readers to be tested under the above conditions. Of course, a system for achieving the above objectives will also be safe for the operator, the vehicle, and the surrounding area.